There are a couple of recording and documents out there to give you a good start in using our reporting tools. The only drawback about them is: You have to know that they exist. So let me list a few of these resources here:

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  A report-designer tutorial, showing how to get started with the Pentaho Report Designer and the built in Report Design Wizard.
  
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  Kurtis Cruzada explains the Drill-Linking.
  
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  Michael Tarallo teaches how to build Guided Adhoc reporting solutions. This covers how to use Parameter, Advanced Datasources and computed queries. At the end you have learned how to implement user-controlled sorting in Pentaho Reporting.
  
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  Along the same line of thought: Michael Tarallo shows how to build a simple What-If analysis report.
  
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  David Kincade showcases the Pentaho Reporting SDK and the walks you through the samples provided in the SDK.
  
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  Our Wiki lists a couple of excellent blog-posts as well. The Wiki will get a overhaul in a few weeks time to update its content to the latest release (and to get rid of the old PRD-3.0 and earlier documentation that is misleading these days).
• and last but not least: Remember there is a book out there that covers all the details: Will Gorman’s Pentaho Reporting 3.5 for Java Developers